It is known to provide devices for preventing a cow from littering its stall floor with excrements. For this purpose, rear manure pits or gutters are provided at the rear end of the cow stall, wherein the cow is to evacuate, the stall floor thus remaining free of cow excrements. This littering prevention is especially desirable in the dairy industry, for the dug of the cow to remain clean and free of bacterial contamination; if the stall floor is littered with excrements, the dug of the cow is likely to become infected since the cow will eventually lie down and come in full contact with its underside with the stall floor.
A device to prevent the cow from littering its stall floor is shown in U.S. Pat. No. 4,967,693 issued in 1990 to Louis A. Prue. Prue discloses a transverse bar to be positioned spacedly and proximately over the back of the cow, the bar being attached by means of three intermediate serially-connected rods to a fixed post of the cow stall. By selectively adjusting the angular relationship between each intermediate rod, the bar can be fixedly positioned over the back of the cow at a suitable location, so that the transverse bar prevent the cow from arching its back. Indeed, since the cow needs to arch its back when evacuating, preventing the cow from arching its back effectively prevents the cow from evacuating at the position where the transverse bar prevents back arching.
In use, Prue teaches that the cow in need to evacuate will move backwards until its back clears the overhanging transverse bar, the hind portion of the cow then being positioned over the gutter, where the cow can evacuate without littering its stall floor. However, the reality is often different: the back of the cow becomes arched at the most of several inches, and thus the transverse bar must be positioned very precisely for it to be operative. The cow may thus arch its back into abutment with the transverse bar, and still be able to evacuate.